The present invention is related to a reel ruler structure that includes a casing, a push element pivotally installed therein with an edge extended outside, a compressing element pivotally positioned inside the casing, a linkage pivotally connected with both the push element and the compressing element for a linked movement, and an elastic element installed in between the push element and the casing so as to enable the compressing element to secure a ruler. A pressing to the push element will release the ruler for a short period of time and a relief to the push element will reset the compressing element and the push element by the elastic element. An enhancement of both convenience and safety in operating the reel ruler is thus achieved.